Move MBEDTLS_ERR_xxx Doxygen comments before the definition

Now that descriptions of error codes no longer have to be on the same line
for the sake of generate_errors.pl, move them to their own line before the
definition. This aligns them with what we do for other definitions, and
means that we no longer need to have very long lines containing both the C
definition and the comment.

```
perl -i -pe 's~^(#define +MBEDTLS_ERR_\w+ +-\w+) */\*[*!]<(.*)\*/~/**$2*/\n$1~' include/mbedtls/*.h
```

This commit does not change the output of generate_errors.pl.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/include/mbedtls/ecp.h b/include/mbedtls/ecp.h
index 06880a0..0924341 100644
--- a/include/mbedtls/ecp.h
+++ b/include/mbedtls/ecp.h
@@ -45,19 +45,29 @@
 /*
  * ECP error codes
  */
-#define MBEDTLS_ERR_ECP_BAD_INPUT_DATA                    -0x4F80  /**< Bad input parameters to function. */
-#define MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL                  -0x4F00  /**< The buffer is too small to write to. */
-#define MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE               -0x4E80  /**< The requested feature is not available, for example, the requested curve is not supported. */
-#define MBEDTLS_ERR_ECP_VERIFY_FAILED                     -0x4E00  /**< The signature is not valid. */
-#define MBEDTLS_ERR_ECP_ALLOC_FAILED                      -0x4D80  /**< Memory allocation failed. */
-#define MBEDTLS_ERR_ECP_RANDOM_FAILED                     -0x4D00  /**< Generation of random value, such as ephemeral key, failed. */
-#define MBEDTLS_ERR_ECP_INVALID_KEY                       -0x4C80  /**< Invalid private or public key. */
-#define MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH                  -0x4C00  /**< The buffer contains a valid signature followed by more data. */
+/** Bad input parameters to function. */
+#define MBEDTLS_ERR_ECP_BAD_INPUT_DATA                    -0x4F80
+/** The buffer is too small to write to. */
+#define MBEDTLS_ERR_ECP_BUFFER_TOO_SMALL                  -0x4F00
+/** The requested feature is not available, for example, the requested curve is not supported. */
+#define MBEDTLS_ERR_ECP_FEATURE_UNAVAILABLE               -0x4E80
+/** The signature is not valid. */
+#define MBEDTLS_ERR_ECP_VERIFY_FAILED                     -0x4E00
+/** Memory allocation failed. */
+#define MBEDTLS_ERR_ECP_ALLOC_FAILED                      -0x4D80
+/** Generation of random value, such as ephemeral key, failed. */
+#define MBEDTLS_ERR_ECP_RANDOM_FAILED                     -0x4D00
+/** Invalid private or public key. */
+#define MBEDTLS_ERR_ECP_INVALID_KEY                       -0x4C80
+/** The buffer contains a valid signature followed by more data. */
+#define MBEDTLS_ERR_ECP_SIG_LEN_MISMATCH                  -0x4C00
 
 /* MBEDTLS_ERR_ECP_HW_ACCEL_FAILED is deprecated and should not be used. */
-#define MBEDTLS_ERR_ECP_HW_ACCEL_FAILED                   -0x4B80  /**< The ECP hardware accelerator failed. */
+/** The ECP hardware accelerator failed. */
+#define MBEDTLS_ERR_ECP_HW_ACCEL_FAILED                   -0x4B80
 
-#define MBEDTLS_ERR_ECP_IN_PROGRESS                       -0x4B00  /**< Operation in progress, call again with the same parameters to continue. */
+/** Operation in progress, call again with the same parameters to continue. */
+#define MBEDTLS_ERR_ECP_IN_PROGRESS                       -0x4B00
 
 /* Flags indicating whether to include code that is specific to certain
  * types of curves. These flags are for internal library use only. */